In the field of general illumination, the widespread use of conventional incandescent light bulbs is giving way to use of fluorescent lamps, which are energy efficient and have a longer life expectancy. In recent years, demand for even greater energy efficiency and life expectancy has spurred research and development of lamps that use an LED. In particular, development of compact LED lamps, which can be used directly in existing light bulb sockets, is progressing (see, for example, Patent Literature 1). The structure of a compact LED lamp according to conventional technology is described with reference to FIG. 13.
As shown in FIG. 13, in a compact LED lamp, an LED module 910 is mounted on an upper surface 920a of a holder 920 and surrounded by a globe 970. An E screw base 940 is attached to the lower section of the holder 920.
A groove 920b is formed at the upper surface 920a of the holder 920 to surround the LED module 910. A rim 970b of the globe 970 is inserted into the groove 920b, and a gap between the groove 920b and the globe 970 is packed with an adhesive 980. By allowing the adhesive 980 to harden, the holder 920 and the globe 970 bond.